	struct msgheader
	{
		uint8_t type;
		uint16_t size;
	};

		// tpye =1
		struct Order
		{
			int a;
		};
		// type =2
		struct Transaction
		{
			int b;
			int c;
		};
		// narket data
		struct InflateL5TickData
		{
			int d;
			int e;
			int f;
		};

		union Union_data
		{
			Order order;
			Transaction trans;
			InflateL5TickData inf;
		};
		struct  c_shm_msg
		{
			msgheader head;
			Union_data data;
		};